What to Look for in Computer MIDI Support

Microsoft recommends that sound cards for both consumer and developer systems include the following:

• General MIDI support. General MIDI refers to a system of assigning numbers to each kind of instrument, so that, for example, instrument 12 on one computer is the same as instrument 12 on all others.
• Polyphony, which means the ability to play multiple sounds at the same time. Consumer systems should include 16-voice polyphony; developer systems should include at least 20-voice polyphony. Support for more concurrent sounds means a fuller-sounding playback.
• MIDI streams. This is an efficient, new capability in Windows 95 whereby a sound card receives and batch-processes multiple MIDI messages (such as Note On and Note Off). With MIDI-stream sound support in the sound subsystem, the CPU is freed from managing those messages individually. This offers virtually flawless playback, even when the CPU is being heavily taxed by large-frame video playback.
• Sampled sound rather than waveform synthesis. Sampled sound is an actual recording of a sound. Waveform synthesis uses a mathematical approximation of that sound.
• Standard MIDI port. Consumers and developers use this port to plug in MIDI devices, such as piano-style keyboards. It also supports joysticks.